Conventionally, as a plasma processing device of the foregoing type, there is known a device capable of improving the uniformity in an etching or vapor deposition process in the plasma chemical technology (for example, see the Patent Document 1).
Patent Document 1: Specification of U.S. Pat. No. 4,264,393
A plasma CVD device used for manufacturing a semiconductor thin film is generally provided with a cathode and an anode which are provided and supported as a pair, a device for applying high-frequency power to one of the cathode and the anode each having a flat-plate shape, and a device for supplying a reactant gas for the formation of the thin film. In the plasma CVD device, plasma is generated in such a manner that high-frequency power is applied while the reactant gas is supplied between the cathode and the anode. As a result, a thin film is generated on a surface of a substrate provided between the cathode and the anode.
A distance between the cathode and the anode is referred to as an inter-electrode distance. The inter-electrode distance includes a certain range where plasma can be effectively generated. In the range, the inter-electrode distance is controlled, and the distance is desirably controlled as accurately as possible. The inter-electrode distance is generally controlled with accuracy in the order of 1/100 relative to the inter-electrode distance, in other words, with accuracy of approximately 1% of the inter-electrode distance. In a method of controlling the inter-electrode distance, a sufficient level of rigidity of the cathode and the anode, which are electrodes, is secured relative to their sizes, so that any deflection is not generated in the provided cathode and anode.